require 'digest/sha1'
class User < ActiveRecord::Base
  has_many :identities
  has_many :presences, :order => 'created_at ASC'
  has_many :activities
  has_many :sent_pings, :class_name => 'Ping'
  has_many :received_pings, :class_name => 'Ping', :foreign_key => 'recipient_id'
  
  # Virtual attribute for the unencrypted password
  attr_accessor :password

  validates_presence_of     :login, :email, :phone
  validates_presence_of     :password,                   :if => :password_required?
  validates_presence_of     :password_confirmation,      :if => :password_required?
  validates_length_of       :password, :within => 4..40, :if => :password_required?
  validates_confirmation_of :password,                   :if => :password_required?
  validates_length_of       :login,    :within => 3..40
  validates_length_of       :email,    :within => 3..100
  validates_uniqueness_of   :login, :email, :case_sensitive => false
  before_save :encrypt_password
  
  # prevents a user from submitting a crafted form that bypasses activation
  # anything else you want your user to change should be added here.
  attr_accessible :login, :email, :password, :password_confirmation, :phone
  
  # Authenticates a user by their login name and unencrypted password.  Returns the user or nil.
  def self.authenticate(login, password)
    u = find_by_login(login) # need to get the salt
    u && u.authenticated?(password) ? u : nil
  end

  # Encrypts some data with the salt.
  def self.encrypt(password, salt)
    Digest::SHA1.hexdigest("--#{salt}--#{password}--")
  end

  # Encrypts the password with the user salt
  def encrypt(password)
    self.class.encrypt(password, salt)
  end

  def authenticated?(password)
    crypted_password == encrypt(password)
  end

  def remember_token?
    remember_token_expires_at && Time.now.utc < remember_token_expires_at 
  end

  # These create and unset the fields required for remembering users between browser closes
  def remember_me
    remember_me_for 2.weeks
  end

  def remember_me_for(time)
    remember_me_until time.from_now.utc
  end

  def remember_me_until(time)
    self.remember_token_expires_at = time
    self.remember_token            = encrypt("#{email}--#{remember_token_expires_at}")
    save(false)
  end

  def forget_me
    self.remember_token_expires_at = nil
    self.remember_token            = nil
    save(false)
  end
  
  def self.find_latest
    find(:all, :order=> 'created_at DESC', :limit => 10)
  end
  
  def self.find_by_identity(identity)
      find(:first, :select => 'users.id AS id, users.login AS login, users.email AS email, users.phone AS phone, i.service', :joins => ["INNER JOIN identities AS i ON (i.user_id = users.id  AND i.login = '#{identity}')"])
  end

  def aka(service)
    connection_identity = identities.select{ |i| 
      i.service == service
    }.first
    
    "#{connection_identity.login}@#{connection_identity.service[0,1]}"
    
  end
  
  
  def aggregate_contacts
    contacts = []
    
    identities.each do |i|
      i.contacts.each do |c|
        contacts << c
      end
    end
    
    contacts.sort! { |x,y| x.username <=> y.username}
  
  end
  
    
  
  def latest_known_location
    presences.last.identifier
  end
  
  def state
    (presences.last.active?) ? 'online' : 'offline' unless presences.blank?
  end
  
  def online?
    (state == 'online') ? true : false
  end
  
  def self.coexist?(foo,bar)
    return (foo.online? and bar.online? and (foo.latest_known_location == bar.latest_known_location)) ? true : false
  end
  
  def self.connected?(foo, bar, service = nil)
    sql = "SELECT COUNT(id) FROM connections AS c WHERE ((left_side_user = #{foo.id} AND right_side_user = #{bar.id}) OR (left_side_user = #{bar.id} AND right_side_user = #{foo.id}))" 
    sql += " AND c.service = '#{service}'" unless service.nil?
    return (count_by_sql(sql) > 0) ? true : false
  end

  protected
    # before filter 
    def encrypt_password
      return if password.blank?
      self.salt = Digest::SHA1.hexdigest("--#{Time.now.to_s}--#{login}--") if new_record?
      self.crypted_password = encrypt(password)
    end
    
    def password_required?
      crypted_password.blank? || !password.blank?
    end
    
end
